Generally described, user computing devices may facilitate the playback or display of items of content, such as audiobooks, electronic books, songs, videos, television programs, computer and video games, multi-media content, and the like. For example, an e-reader user computing device may display an electronic book on a screen or play an audiobook through speakers or headphones. In some instances, the publisher or author of an item of content may provide supplemental content to accompany the item of content, such as a soundtrack, video clip, multi-media content, etc. This supplemental content may be played by the user computing device as the user consumes the item of content.
In some current approaches, this supplemental content is created specifically for an item of content. For example, a soundtrack for a particular electronic book or audiobook may be recorded and synchronized to that electronic book or audiobook. However, this approach can be time-consuming and expensive, possibly requiring the generation of new supplemental content for each item of content to be enhanced. This purpose-generated supplemental content may become “stale” for a user of the content, especially in cases where only a small amount of supplemental content is generated for the item of content. Moreover, if the user dislikes the supplemental content provided with an item of content, he or she may have no recourse other than to disable the supplemental content. Likewise, users that wish to customize the supplemental content may not have the opportunity to do so under these approaches.